It has heretofore been proposed as in U.S. Pat. No. 2,909,003 to Marshall of Oct. 20, 1959, to provide a grass seed mat with a layer of compressed textile fibers containing grass seed locked in the compacted fibers thereof, the fibrous layer being covered on one or both sides by layers of water permeable material and the mat permitting free passage of water.
It has also been proposed in U.S. Pat. No. 2,822,644 to Berger of Feb. 11, 1958, to provide a plant protector for encircling a tree, the protector being formed of thin, resilient water impervious material having annular, concentric ribs and grooves, with drainage apertures in the bottoms of the grooves. A similar tree collar, or protector, is disclosed in U.S. Pat. No. 3,305,969 to Mattson of Feb. 28, 1967, the slit collar having a lower layer of compressibly, resilient porous material and an upper layer of thin plastic film, impervious to passage of moisture in a dished configuration.
Mulch carpets permitting free passage of water not only tend to let rain wash out beneath the mulch but also permit moisture to freely evaporate through the mulch to thereby dry out the ground around the plants. On the other hand, mulch which does not permit passage of any water, or transpiration of any moisture except at a central cut out, tends also to dry out the ground and deny water to rootlets located away from the cut outs.